Railroad car retarders



Feb. 2, 1965 F. w. CREEDLE RAILROAD CAR RETARDERS 4 Sheets-Sheet l Filed Dec. 4, 1962 INVENTOR. FRED W. CREEDLE Feb. 2, 1965 F. w. CREEDLE 3,168,166

RAILROAD CAR RETARDERS Filed DeC. 4, 1962 4 Sheets-Sheet 2 INVENTOR. FRED W. CREEDLE FFL- LL/E- Feb. 2, 1965 F. w. CREEDLE 3,168,166

RAILROAD CAR RETARDERS INVENTOR. FRED W. CPJ-:EDLE

M Mig/ Feb. 2, 1965 F. w. CRI-:EDLE 3,168,166

RAILROAD CAR RETARDERS Filed Dec. 4. 1962 4 Sheets-Sheet 4 INVENTOR. FRED VV. CREEDLE United States Patent O 3,168,166 RAILROAD CAR RETARDERS Fred W. Creedle, Park Ridge, Ill., assigner to American Brake Shoe Company, New York, N.Y., a corporation of Delaware Filed Dec. 4, 1962, Ser. No. 242,133 Claims. (Cl. 188-62) This invention relates to a new and improved railroad car retarder and more particularly to a car retarder actuated directly in response to the weight of a car traversing the retarder.

Railroad car retarders are commonly used in railroad classification yards and in similar locations to brake cars that have been separated from a train and continue to roll toward a classification track or other location. The retarders are sometimes actuated by springs or by control systems responsive to the speed, weight, or other factors relative to the car or cars being braked. Because a heavy car requires a greater braking force than a light car, in order to achieve a given deceleration, it is frequently advantageous to actuate the retarder directly in response to the car weight. On the other hand, complexity in the weight sensing and retarder actuating apparatus is highly undesirable because it may well lead to failure of the retarding apparatus under critical conditions.

It is an object of the present invention, therefore, to provide a new and improved weight-responsive railway car retarder that is simple in construction, as compared with previously known devices, and is inherently reliable in operation.

A further object of the invention is to afford a weight responsive railway car retarder that provides balanced braking forces applied to two retarder rails by means of a direct mechanical linkage of balanced construction between the traffic rail and the retarder rails.

Another object 'of the invention is to afford a balanced, weight-responsive railway car retarder construction that inherently minimizes difficulties due to adverse weather conditions and other factors present in railway operations.

Other and further objects of the present invention lwill be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show a preferred embodiment of the present invention and the principles thereof and what is now considered to be the best mode contemplated for applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

FIG. 1 is a plan view of a weight-responsive railway car retarder constructed in accordance with one embodiment of the present invention;

FIG. 2 is a sectional view of a part of the car retarder, taken approximately along line 2-2 in FIG. 1;

FIG. 3 is a sectional view taken approximately along line 3-3 in FIG. 1;

FIG. 4 is a sectional view, taken approximately along line 4-4 in FIG. 1, showing the weight-responsive drive mechanism of the invention in one operational position;

FIG. 5 is a view similar to FIG. 4 but illustrating the retarder mechanism in a second operating position; and

FIG. 6 is an end view of a part of the retarder apparatus taken approximately as indicated by line 6-6 in FIG. 4.

FIG. l illustrates a weight-responsive railway car retarder 10 constructed in accordance with one embodiment 'of the present invention. Retarder 10 is incorporated in a section of a railway track comprising a plurality of individual ties 11 and a pair of traffic rails 12 and 13.

3,168,166 Patented Feb. 2, 1965 'ice Trac rail 12 is continuous and may be mounted in fixed position upon ties 11 by any suitable conventional means. Traffic rail 13, on the other hand, does not contlnue uninterrupted through retarder 10, but is provided with an intermediate segment 14 that is mounted within the retarder in a manner substantially different from that employed in connection with traffic rail 12, as explained more fully hereinafter.

At one side of retarder 16 there is mounted a guard rail 15. Guard rail 15 is of fixed construction and is supported upon a plurality of guard chucks 16. Guard rail 15 serves only to guide movement of a railway car through the retarder and is not utilized to apply a braking force to the car. The ends of the guard rail are preferably ared inwardly of the railway and may be provided with suitable foot guards 17 if desired.

The working apparatus of retarder 1@ is aligned along the segment 14 of traffic rail 13. The braking apparatus includes a pair of retarder rails 18 and 19 that extend through and are supported at a plurality of operating stations 21, 22, 23 and 24 within the retarder. Although only four operating stations are shown in FIG. l, it should be understood that additional similar stations may be employed if desired, particularly if a longer retarder is to be provided. In the embodiment illustrated in FIG. 1, stations 21 and 24 are substantially similar in construction and stations 22 and 23 are also similar to each other, although different from stations 21 and 24. Accordingly, only the operating mechanisms of stations 21 and 22 are described in detail hereinafter.

The construction and operation of retarder operating station 21 can best be understood by reference to FIGS. 2 and 3, taken in conjunction with FIG. l. As shown therein, this operating station of retarder 10 comprises a fixed frame member 25 affixed -to the tie 11A. Frame member 25, sometimes referred to hereinafter as a chain includes a top plate 26 supported upon the top of the tie 11A. The chair further includes a pair 'of depending flanges or side plates 27 and 2S that extend downwardly along the sides of the tie, so that the upper portion of the tie is in effect embraced by the plates 26, 27 and 28. The chair is a unitary one-piece casting adapted to easy placement on the tie; moreover, the upper plate 26 of the chair is provided with a plurality of suitable apertures to permit the chair to be anchored to the tie by suitable spikes, studs, or like members 29 (see FIG. 1).

As shown in FIGS. l-3, chair 25 is provided with four upstanding lugs 31, 32, 33 and 34. Lugs 32 and 34 are located at one side of the position of trafc rail 14 and lugs 31 and 33 are located on the opposite side of the traic rail. Lugs 31 and 33 are provided with aligned apertures for receiving a pivot pin or shaft 35 and a similar shaft 36 is mounted in lugs 32 and 34. Shafts 35 and 36 are held in mounted position in the support lugs of the chair by suitable means such as the cotter pins 37. Individual end washers 38 may be utilized in conjunction with the shafts to prevent excessive axial movement thereof.

As shown in FIG. 2, a pair of support levers or arms 41 and 42 are pivotally mounted upon shafts 35 and 36, respectively, on the outboard ends of the shafts between their respective washers 38 and support lugs 31 and 32, respectively. The upper end of lever 41 is aixed to rail 19 to provide a pivotal support for the retarder rail. Similarly, the upper end of arm 42 is affixed to retarder rail 18 and affords a pivotal support for that rail. The lower ends of levers 41 and 42 project below the top plate 26 of chair 25 and are interconnected by a connecting rod 44. Connecting rod 44 is supported within relatively larger apertures in the lower ends of arms 41 and 42 so that the ends of the arms are slidably movable along QT; the connecting rod. A spring 45 is mounted upon connecting rod 44 in encompassing relation thereto and engages the lower ends of levers 41 and 42, tending to maintain themin the position illustrated in FIG. 2. A cylinf d'rical stop member 46 is disposed within the spring 45 and is utilized to limit inward movement of the lower ends of the levers 41 and 42 during operation of the retarder and thereby prevent bottoming of the spring.

' At the other side of operating .station 21, as shown in FIG. 3, a crank member 48 is pivotally mounted upon shaft 36 between washer 38 and chair lug 34. The upper end of crank 48 is affixed to retarder rail 18 and provides a further pivotal support for the retarder rail. A ysimilar crank member 49 is lpivotally mounted upon shaft 35, at the outboard end of the shaft between washer 38 and chair lug 33. The upper end of this crank is secured to rail 19. and provides a further pivotal support for this retarder rail.

At the lower end of crank 48, which projects well below the top plate 26 of chair 25, a clevis or yoke 51 is pivotally connected to the crank by suitable means such as a pin 52. On the opposite side of operating station 21, a second yoke 53 is pivotally connected to the lower end ofcrank 49 by means of a pin 54. n

A fluid pressure operated cylinder 55 is mounted upon yoke 54 by suitable mounting means such as the bolts 56. .Cylinder 55 houses an operating piston (not shown) on a piston rod 57 that projects -outwardly of the cylinder and is connected to yoke 51 as by a threaded connection including a nut 58. The connection between piston rod 57 and clevis 51 is preferably adjustable in length so that the position of the piston rod within the cylinder can be adjusted t0 one extreme for the normal un-opera-ted position of the retarder, illustrated in both of FIGS. Zand 3 and normally maintained by the biasing spring 45.

As thus far described, retarder 10 is substantially similar in construction to the retarder apparatus described and claimed in the co-pending application of Rosser L. Wilson, Fred W. Creedle, and John R. Wilhelm, Serial No. 154,538, led November 24, 1961. That is, the construction of chair 25, and the mounting of retarder rails 18 and 19 thereon, together with the location and mounting of bias spring 45 and operating cylinder 55, are all substantially similar to the corresponding structures shown in the aforementioned application. Biasing spring 45,- bearing against the lower ends of arms 41 and 42, tends to maintain retarder rails 18 and 19 in the position illustrated int FIGS. 2 and 3,in which the space between the retarder rails is substantially smaller than the thickness of a railway vehicle wheel. Cylinder 55, on the other hand, can be utilized to pivot cranks 48 and 49 relative to their respective shafts 36 and 35 to move the retarder rails outwardly with respect to the position of traic rail 14. In the retarder of the present invention, unlike that of the aforementioned application Serial No. 154,538, the iluid operated cylinder .is employed only to open the retarder by moving rails 18 and 19 away from each other; it does not lapply the retarding force necessary to accomplish a braking operation. Instead, the braking force is effected by the apparatus illustrated in FIGS. 4-6.

FIG. 4 illustrates the weight-responsive braking mechanism of the present invention'in its normal or unactuated operating condition. This portion of the retarder comprises a xed frame member or chair 25 having twovertcally depending side plates 27 and 28 joined across the top by a top plate 26. As shown in FIG. 6, plates 27 and 28 are disposed on opposite sides of a tie 11B. On the top of chair 25, the chair is again provided with upstanding lugs corresponding to lugs 31-34 as described hereinbefore in connection with FIGS. 1-3. As before, a shaft 35 is journalled in the upright lugs at one side of the frame member 25 and asimilar shaft 36 extends between `lugs 32 and 34 at the opposite side of the chair (see FIGS. 4 and 6). At the right-hand side of Ichair. 25, as viewed in FIG. 6, there is mounted a fluid pressure operated mechanism forfopening the retarder,

only the clevis 51 and the pivot pin 52 afxed to crank 48 appearing in this gure.

At the opposite side of chair 25 from crank 48, a seeond crank 68 is journalled on shaft 36. Crank 68 is.es sentially similar in construction to crank 48 and includes an upwardly projecting portion to which retarder rail 18 is secured, affording a support for this retarder rail. At the opposite side of traffic rail 14, as seen in FIG. 4, a similar crank, V69 is pivotally mounted upon shaft 35. Crank 69 includes an upwardly projecting portion to which retarder rail 19 is secured, thereby providing an additional pivotal support for this retarder rail.

At the lower end of crank 69, well below the top plate 26 of chair 25, a clevis 71 is pivotally mounted upon the crank by suitable means such as a pivot pin 73. A connecting rod 75 connects clevis 71 to a second clevis or yoke member 77 Ythat is pivotally mounted upon a traffic rail support block 80 by means of a pivot pin 79.

A similar linkage is provided at the right-hand side of the mechanism, as viewed in FIG. 4, connecting support -block 80 to the lower end of crank 68. Thus, a clevis 72 is pivotally mounted upon the lower end of crank 68 by means of a pivot pin 74, and this rst clevis is connected to a second yoke 78 by means of a connecting rod 76. Yoke 78 is connected to support block Srtlby a suitable pivot pin 82. The pivotal Vconnections Iof the connecting rods to the crank arms, comprising pins 73 and 74, are located below the pivot pins 79, 82 connecting the rods to block 80. Y

. In retarder 10, traflcrail 14 is not mounted directly 'upon the ties 11, nor is it secured to the frame members or chairs 25. Instead, and as clearly shown in FIG. 4, traic rail 14 rests upon and is supported by support blocks 80.Y Preferably, downward movement of the traic rail is limited by Vsuitable means such as a series of tie pads 81 mounted upon chairs 25 (see FIGS. 2 and 3). But the traflc rail is free to move upwardly of the position shown in FIG. 4 in response to upward movement of support blocks rSi), as described more fully hereinafter.

It is not desirable to permit substantial horizontal movement of the traic rail, however, since this must be maintained at the desired gauge spacing relative .to the other trailc rail 12 (FIG. l). To this end, a guide arm 84 is pivotally mounted upon shaft 36 between crank 68 and the cotter pin 37 at this end of the shaft (see FIGS. 4-6). Guide arm 84 projects inwardly of the retarder apparatus,

toward trac rail 14, and is provided with an elongated slot 85 at the forward end thereof, as shown in the central cut-away portion of FIG. 4.

A guide bracket 86 is xedly mounted upon traic rail 14, being secured to the web portion of the rail by suitable means such as a pair of mounting plates 87 and suit able retaining bolts 88.- Br-acket 876V includes a pair of lugs 89 projecting on opposite sides of guide arm 84; a pin 91 extends between the two lugs 89, passing through the slot 85 in the guide arm. In this manner, guide arm 84 serves to prevent any substantiall horizontal movement of traffic rail 14 and maintains the traic rail in the desired position relative to the other rail of lthe railway.

As knoted hereinabove, retarder rails 18 and 19 Vare normally maintained in the position illustrated in FIGS. 2, 3 and 4, with the spacing between the retarder rails, at the edges adjacent tratc rail 14, narrower than the width of a railway vehicle wheel. When a railway vehicle enters the retarder, the leading wheel rst comes between the ilared ends of the retarder rails 18 and 19 (see FIG. l). Accordingly, the lead wheel of the car tends to force rails 18 and 19 away from each other. Because the two retarder rails are both pivotally mounted, they can'rnove away from the face surfaces of the vehicle wheel, permitting the wheel to move into the space between the retarder rails.

The foregoing operation, with a car wheel moving between the retarder rails, tends to pivot arm 68 in a clockwise direction .about its shaft 36 and to pivot arm 69 in a counterclockwise direction about shaft 35, due to the outward movement of the retarder rails 18 and 19 respectively. But the pivotal movement of cranks 68 and 69 forces support block 80 upwardly, moving the support block toward a position such as that illustrated in FIG. 5. The weight of the car, on the other hand, is directly opposed to upward movement of traffic rail 14, since the car is supported upon this section of the traflic rail. Thus, the weight carried by car wheel 95 (FIG. 5) acts downwardly upon traffic rail 14 and is resolved into substantially equal forces driving retarder r-ails 18 vand 19 into engagement with the opposed faces of car wheel 95. The braking force developed by frictional engagement between the retarder rails and the car wheel is thus directly proportional to the weight of the car.

At least one of the connecting rods 75, 76 should be adjustable in length in order to balance the leverage ratios and to attain a workable braking ratio for the apparatus. Thus, if the mechanical advantage afforded by the two balanced lever systems is too great, braking will be excessive and the car wheels may be damaged or cars may be squeezed completely out of the retarder. If the mechanical advantage is too low, insufficient braking may result. In FIGS. 4 and 5, both connecting rods are of adjustable length construction, but it is usually sufficient to provide for adjustment of one if block Si) is substantially longer than the base width of rail 14.

After the car passes through the retarder, the retarder is restored to its initial operating position by the biasing springs such as spring in the illustrated embodiment, there are only two springs located on operating stations 21-2li, but additional springs may be utilized if the size, weight, and length of the retarder makes this necessary. If a car is brought to a complete stop in the retarder, or if a locomotive or other railway vehicle is to be moved through the retarder without braking, then the operating cylinders such as cylinder may be employed to open the retarder, working against the biasing springs 45. In the embodiment illustrated in FIG. l, there are four such operating cyiinders, one located at each of stations 21 through 24, but it is not essential that an operating cylinder be provided at each such station. Instead, a smaller number may be utilized if operating cylinders of sufficient capacity are employed.

Normal application of the retarder is effected by the operating mechanism described in detail in connection with FIGS. 4 and 5 and by corresponding apparatus incorporated in operating station 23 of retarder 10. Again, however, it is not a critical requirement of the invention that this specific number of weight-responsive brake applying mechanisms be employed. In a short retarder, it might be possible to operate with only one weight sensing mechanism, whereas in a larger installation it is usually desirable to use three or more brake applying devices.

The weight-responsive retarder operating mechanism of FGS. 4-6 is simple and economical in construction, being comprised essentially of ordinary levers and other conventional structural members. However, the device affords an inherent balanced braking application, since the two retarder rails 18 and 19 are mounted upon and -supported by similar crank members that are connected to the support blocks Sti by essentially identical linkages. There are no sliding connections to become blocked with dirt or refuse; all operations are carried out by means of simple rotary movements, so that the working members can be easily protected and lubricated. There is no mechanical connection between traffic rail 14 and the operating levers that apply the braking force through either of the rails 1S and 19 (guide arm 84 serves only to prevent lateral movement of the trafiic rail and is independently rotatable relative to crank 63). Consequently, the operating mechanism affords highly reliable operation despite the inexpensive construction employed.

Hence, while preferred embodiments of the invention have been described and illustrated, it Iis to be understood that they are capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

h 1. A weight-responsive railway car retarder comprising:

a xed frame member straddling one traffic rail position of a railway section, said frame member having a pair of vertically extending substantially similar crank members pivotally mounted thereon in opposed spaced relation at opposite sides of the traffic rail position;

a pair of retarder rails each affixed to and supported by the upper end of the crank member on a respective side of the trafiic rail position;

a traflic rail support block being disposed beneath the traffic rail, said trafiic rail being at the height of said pivotal mountings for said crank members;

a pair of connecting rods pivotally connected to the lower ends of respective ones of said pair of crank members and each pivotally connected to said support block, said connecting rods being of approximately equal length;

and a tratiic rail resting on and supported by said support block, at said trafiic rail position between said retarder rails, whereby the downward force on said traffic rail resulting from the weight of a railway car wheel traversing said trafc rail is resolved into two substantially equal forces urging said retarder rails together into frictional engagement against the opposed sides of said wheel.

2. A weight-responsive railway car retarder comprisa plurality of fixed frame members disposed at spaced intervals straddling one traffic rail position of a railway section of given length, each frame member having a pair of vertically extending substantially similar crank members pivotally mounted thereon in opposed spaced relation at opposite sides of the trafiic rail position;

a pair of retarder rails, each afiixed to and supported by the upper ends of the crank members on a respective side of the trafiic rail position;

a plurality of traffic rail support blocks being connected to said traffic rail, said traffic rail being at the height of said pivotal mountings for said crank members and spaced adjacent to cross ties;

means for connecting each support block to the lower ends of one pair of said crank members, said means comprising a pair of connecting rods of approximately equal length each pivotally connected at opposite ends to the block and to the associated crank, the pivotal connections between said rods and said cranks being located below the pivotal connections between said rods and said block;

and a trafiic rail resting on and supported by said support blocks at said traffic rail position between said retarder rails, whereby the downward force on said traffic rail resulting from the weight of a railway car wheel traversing said trafiic rail is resolved into two substantially equal forces urging said retarder rails toward each other and into frictional engagement against the opposed sides of said wheel.

3. A weight-responsive railway car retarder comprisa plurality of fixed frame members disposed at spaced intervals straddling one traffic rail position of a railway section of given length, each frame member having a pair of vertically extending substantially similar crank members pivotally mounted thereon in opposed spaced relation at opposite sides of the traffic rail position, each of said crank members pro- 7 jecting above and'below the base level of the traiic rail position;

a pair of retarder rails, each affixed to and supported by the upper ends of the crank members on a respective side of the traic rail position;

bias means normally yieldably maintaining said retarder rails at a spacing narrowerthan the thickness of a railway vehicle wheel;

a plurality of traic rail support blocks, each of said blocks being disposed beneath a traic rail and to lift said traffic rail from its support on said frame members;

means for connecting each support block to the lower ends of one pair of said crank members, said means comprising a pair of connecting rods of approximately equal' length each pivotally connected at opposite ends to the block and to the associated crank, the pivotal connections between said rods and said cranksbeing located below the pivotal connections between said rods and said block;

a traic rail resting on and supported by said support blocks at said traic rail position between said retarder rails, whereby the downward force on said tratiic rail resulting from the weight of a railway car wheel traversing said traflic rail is resolved into two substantially equal forces urging said retarder rails toward each lother andinto frictional engagement against the opposed sides of said wheel;

and guide means, interconnecting said frame member and said traflicrail, for gmiding vertical movement of said tratic rail and preventing horizontal movement thereof.

4. A weight-responsive railway car retarder comprising:

a plurality of xed frame members disposed at spaced intervals straddling one trafc rail position of a railway section of given length, eachframe member having two pairs of vertically extending substantially similar crank members pivotally mounted thereon with the crank members of each pair disposedV in opposed spaced relation at opposite sides of the trafc rail position;

a pair of retarder rails, each aixed to and supported by the upper ends of all of the crank members on a respective side of the traic rail position;

a plurality of traic rail support blocks;

means for connecting each support block to the lower ends of one pair of said crank members, said means comprising a pair of connecting rods of approximately equal length each pivotally connected at opposite ends to the block and to the associated crank, the pivotal connections between said rods and said cranks being located below the pivotal connections between said rods and said block so that 8 car wheel traversing said't'rai'c rail'is resolved into two substantially equal forces urging said retarder rails toward each other and into frictional engagement against the opposed sides of said wheel;

a plurality of biasing springs, each connected to the lower ends of one pair of said crank members, for normally yieldably maintaining said retarder rails at a spacing less than the thickness of a railway vehicle wheel with the traic rail at its lowermost position;

and means for spreading said retarder rails, against the forces applied thereto by the vehicle weight and by said springs, to permit a vehicle to pass from the retarder without braking.

5. A weight-responsive railway car retarder comprising:

. a plurality of fixed frame members disposed at spaced intervals straddling one trailic rail position of a railway section of given length, each frame member having a pair of verticallyextending substantially similar'crank members pivotally mounted thereon in opposed spaced relationk at opposite sides of the traic rail'position;

a pair of retarder rails, each affixed to and supported by the upper ends of the crank members on a respective side of the trafc rail position;

biasing means normally yieldably maintaining said retarderV rails at a spacing slightly smaller than the thickness of a railway vehicle wheel;

a plurality yof traic rail support blocks;

means for connecting each support block to the lower ends of one pair of said crank members, said means for each block comprising a pair of connecting rods of approximately equal length each pivotally connected at opposite ends to the block and to the associated crank, the pivotal connections between said rods and said cranks being located below the pivotal connections between said rods and said blocks, at least one rod in each pair being adjustable in length to permit adjustment of the normal vertical positionof said support blocks and of the mechanical leverage ratios of said rods and associated crank members;

and a tratiic rail resting on and supported by said support blocks at said traic rail position between said retarder rails, whereby the downward force on said traffic rail resulting from the weight of a railway car Wheel-traversing said traic rail is resolved into twol substantially equal forces urging said retarder rails toward eachother and into frictional engagement against the opposed sides of said wheel.

References Cited in the file of this patent I UNITED STATES PATENTS spreading of said retarder rails raises said support 1,627,137 Barr May 3, 1927 blocks; 1,692,090 Miner Nov. 20, 1928 a traic rail resting on and supported by said Vsupport 2,275,388 Clausen Mar, 10, 1942 blocks at said traffic rail position between said ref tarder rails, whereby the downward force onsaid f FOREI'GIT PATENTS traffic rail resulting from the weight of a railway 649,753 Great Britain Jan. 31, 1951 

1. A WEIGHT-RESPONSIVE RAILWAY CAR RETARDER COMPRISING: A FIXED FRAME MEMBER STRADDLING ONE TRAFFIC RAIL POSITION OF A RAILWAY SECTION, SAID FRAME MEMBER HAVING A PAIR OF VERTICALLY EXTENDING SUBSTANTIALLY SIMILAR CRANK MEMBERS PIVOTALLY MOUNTED THEREON IN OPPOSED SPACED RELATION AT OPPOSITE SIDES OF THE TRAFFIC RAIL POSITION; A PAIR OF RETARDER RAILS EACH AFFIXED TO AND SUPPORTED BY THE UPPER END OF THE CRANK MEMBER ON A RESPECTIVE SIDE OF THE TRAFFIC RAIL POSITION; A TRAFFIC RAIL SUPPORT BLOCK BEING DISPOSED BENEATH THE TRAFFIC RAIL, SAID TRAFFIC RAIL BEING AT THE HEIGHT OF SAID PIVOTAL MOUNTINGS FOR SAD CRANK MEMBERS; A PAIR OF CONNECTING RODS PIVOTALLY CONNECTED TO THE LOWER END OF RESPECTIVE ONES ON SAID PAIR OF CRANK MEMBERS AND EACH PIVOTALLY CONNECTED TO SAID SUPPORT BLOCK, SAID CONNECTING RODS BEING OF APPROXIMATELY EQUAL LENGTH; AND A TRAFFIC RAIL RESTING ON AND SUPPORTED BY SAID SUPPORT BLOCK, AT SAID TRAFFIC RAIL POSITION BETWEEN SAID RETARDER RAILS, WHEREBY THE DOWNWARD FORCE ON SAID TRAFFIC RAIL RESULTING FROM THE WEIGHT OF A RAILWAY CAR WHEEL TRAVERSING SAID TRAFFIC RAIL IS RESOLVED INTO TWO SUBSTANTIALLY EQUAL FORCES URGING SAID RETARDER RAILS TOGETHER INTO FRICTIONAL ENGAGEMENT AGAINST THE OPPOSED SIDES OF SAID WHEEL. 